8 ms·

Elon Musk doesn't understand geometry

24 points by free0ne 3y ago

pjkundert 3y ago
No, Elon does understand geometry — this author doesn’t understand the free market. On the rare occasion that the “public transit” busses sharing our roadways are full, they are indeed very efficient. Unfortunately - these situations are rare. The rest of the time, other solutions are vastly more desirable to the public. Simultaneously, these huge, lumbering 90%-empty beasts pile up traffic behind them, forcing massive exhaust plumes from the unnecessarily idling traffic. Stop subsidizing sub-standard solutions, and let the transit-using public decide.
- hooverd 3y ago
  Alternatively, you could incentive people taking transit by making cars more expensive (by pricing in externalities).
  - fooker 3y ago
    >(by pricing in externalities). In practice, this means someone pockets the change and nothing gets done about the so called externalities.
    - enraged_camel 3y ago
      What do you mean? Can you give examples?
      - fooker 3y ago
        Suppose you want to force people to drive less — you increase gas prices with a tax. Citing this extra tax, some lawmaker spends money on something completely irrelevant that was lobbied to them. Public transport is a fairly distant concern for most of them. Oil companies increase crude prices to get on the gravy train, so does every other entity in the industry. Car dealerships jack up prices because they want to maintain their profit levels. Meanwhile middle class people who rely on cars get effed.
        hooverd 3y ago
        Nah, you do congestion pricing in cities where transit is feasible.
- jcranmer 3y ago
  You don't ride buses much do you? Of all the times I've ridden regular bus routes, there's only been one route where the bus being 90% empty would not be extremely atypical--and even then, that was only when I was picking up the bus during off-peak hours. More frequent have been the times where there being anything other than standing room available was the atypical situation. If you're in an urban environment at least as densely packed as, say, San Jose, then the bus system is likely to have actually quite substantial ridership. By the time you get to the kinds of dense urban environments of the standard major US cities (NYC, Chicago, DC, Philly, Boston), I quite assure that the buses are routinely packed. The story might be different if we're talking about, say, Bismarck. Furthermore, I should point out that if a bus is stopped "pil[ing] up traffic behind them", that's because it's letting passengers embark or disembark, which is a strong signal that the bus probably isn't 90% empty.
  - josephcsible 3y ago
    > Of all the times I've ridden regular bus routes, there's only been one route where the bus being 90% empty would not be extremely atypical You're falling victim to the inspection paradox: https://towardsdatascience.com/the-inspection-paradox-is-everywhere-2ef1c2e9d709 https://towardsdatascience.com/the-inspection-paradox-is-eve...
    - Freedom2 3y ago
      Interesting. What evidence do you have to back up your claim that the user has fallen victim to this paradox?
      - josephcsible 3y ago
        Using your experience as a passenger to gauge how full buses usually are is about as straightforward of an example of that paradox as you could ask for. As an extreme example, imagine there are 10 bus routes, 9 of which are always empty and 1 of which is always full. If you surveyed every passenger, they'd tell you that 100% of the buses they've ever been on are full, but in reality, only 10% of the buses are.
- Zigurd 3y ago
  On-demand AVs will probably kill mass transit in the US. The poor will get the equivalent of EBT cards to ride, so there will be a social aspect to it. But framing it as some kind of Randian triumph ignores that there are places in the world where mass transit is very efficient because the cities are different. Private cars will be for the rich and should be taxed appropriately. Meeting your fellow citizen while riding an AV mini-bus will open your eyes to social diversity.
- caditinpiscinam 3y ago
  There are tons of real-world situations in which individuals, by making choices that benefit themselves, create a situation that is worse for everyone overall. It's basic microeconomics https://en.wikipedia.org/wiki/Tragedy_of_the_commons https://en.wikipedia.org/wiki/Tragedy_of_the_commons
cs702 3y ago
Please don't editorialize the title. The original title is actually "Basics: Technology Never Changes Geometry." The OP's main point is that in dense urban areas, replacing high-capacity vehicles with small-capacity ones presents a geometric challenge, because the surface area covered by streets is fixed. Were we to replace every bus carrying an average of, say, 40 people, with 20 small self-driving vehicles, each carrying an average of two people, the street surface area occupied by the small vehicles will be significantly greater and traffic will slow down to a crawl. Imagine a gazillion small vehicles stopping everywhere to pick up and drop off passengers. As the OP correctly points out, finding ways to use space efficiently is the core problem of urban transportation.
- Phil_Latio 3y ago
  The additional vehicles could simply drive around the "hot" zones...
- quantumwannabe 3y ago
  The author forgot about time. 20 small self-driving vehicles that come every 30 seconds uses no more road space than a 40-person bus that comes every 10 minutes. Musk's self-driving taxi idea also isn't new. It's essentially the same thing as Personal Rapid Transit [1] which was originally envisioned back in the 1950s as a way to solve real world public transit system issues: >Most mass transit systems move people in groups over scheduled routes. This has inherent inefficiencies. For passengers, time is wasted by waiting for the next vehicle to arrive, indirect routes to their destination, stopping for passengers with other destinations, and often confusing or inconsistent schedules. Slowing and accelerating large weights can undermine public transport's benefit to the environment while slowing other traffic. >Personal rapid transit systems attempt to eliminate these wastes by moving small groups nonstop in automated vehicles on fixed tracks. Passengers can ideally board a pod immediately upon arriving at a station, and can – with a sufficiently extensive network of tracks – take relatively direct routes to their destination without stops [1] https://en.wikipedia.org/wiki/Personal_rapid_transit https://en.wikipedia.org/wiki/Personal_rapid_transit
  - jcranmer 3y ago
fooker 3y ago
If policy makers had the authors perfect understanding of geometry : * We would be living in tiny cubicles and sharing amenities with N people (N is a function of whatever factors the authorities deem important.) * Strapped to vertical planks for flights. * Have perfectly circular(/spherical?) cities with poorer people commuting from farther rings. * Work in tiny cubicles (This has already happened, thanks beancounters!). * Children carted away to boarding schools to not disrupt routines of productive people and ensure optimal education (sounds familiar?). * Industrial workers deployed to worksites for N months (N is a function beyond your control..)
- Tade0 3y ago
  My city's traffic planners designed the traffic light phases with safety (and possibly throughput) as their primary concern. Apologies for the caps, but I have very strong feelings about this: THERE'S NOT A SINGLE INTERSECTION THAT I CAN WALK THROUGH IN ONE PHASE People being people just go on red. Drivers run through intersections way past late amber - especially on left turns. Someone assumed spherical humans in a vacuum and is probably happy with the results.
Zigurd 3y ago
there are a few problems with the article: first, busses in US cities are either too full on clogged streets or too empty on empty streets to have an average load factor high enough to make them less polluting than cars. Cars. even ordinary sedans, used as shared robotaxis could readily beat busses environmentally. But once you get purpose-built mini-bus robotaxis, that will dominate in efficiency. I'm all for better social amenities, but, in the US, with maybe a couple exceptions, robot-rides-on-demand is the likely winner, and it will be a near ideal free market: No barriers to entry, relatively low capex to get started, intermediaries enabling any size fleet to get customers, etc.
pierat 3y ago
And by the time you explain it, you've already lost the narrative. A fact that we've learned in the massive social media sphere is that "Louder = right". And, I hate this. Someone screams their viewpoint? They must be right. Someone responds back with trite phrases that catch people? Obviously correct. Someone retorts with an overly simplistic comment? Of course, naturally correct. Someone exerting power in a situation against someone with little power? Might makes right.
Tade0 3y ago
> Musk assumes that transit is an engineering problem, about vehicle design and technology. In fact, providing cost-effective and liberating transportation in cities requires solving a geometry problem. This confusion is very common in transport technology circles. It's actually a psychology problem and I wish more urban/transit planners understood that. You'd be hard-pressed to make buses go bumper to bumper like cars in traffic, meaning there's space to spare even when most people use public transport to move around. Geometry is actually a constraint only on the terminals - parking lots consume a lot of land. Meanwhile people choose to drive not because it's efficient (it's not, far from it), but because for them it has advantages which can't be summarized as a single number like average travel time. If you ask around you'll find that most people don't think too hard about the exact amount of minutes their commute takes. They just want to be on time and once that's taken care of, other factors become more important. To solve this you have to change how public transport is perceived. I'm not American so bear with me here: One way to do it is to give a familiar experience. If statistics are to be believed, half of US K-12 students get to school by bus. Also, people regularly fly. Private transport via air is comparatively rare. This is all mass transit. To me the core features of these two experiences are: -Everyone sits. -Everyone is accounted for. -Changes are minimized, if present at all. -There's a schedule and it's treated seriously. It appears that Elon Musk, despite being generally unhinged, knows more about human nature than transit planners, which is weird, because that's a low bar to clear.

24 points by free0ne 3y ago

No, Elon does understand geometry — this author doesn’t understand the free market. On the rare occasion that the “public transit” busses sharing our roadways are full, they are indeed very efficient. Unfortunately - these situations are rare. The rest of the time, other solutions are vastly more desirable to the public. Simultaneously, these huge, lumbering 90%-empty beasts pile up traffic behind them, forcing massive exhaust plumes from the unnecessarily idling traffic. Stop subsidizing sub-standard solutions, and let the transit-using public decide.

hooverd 3y ago
Alternatively, you could incentive people taking transit by making cars more expensive (by pricing in externalities).
- fooker 3y ago
  >(by pricing in externalities). In practice, this means someone pockets the change and nothing gets done about the so called externalities.
  - enraged_camel 3y ago
    What do you mean? Can you give examples?
    - fooker 3y ago
      Suppose you want to force people to drive less — you increase gas prices with a tax. Citing this extra tax, some lawmaker spends money on something completely irrelevant that was lobbied to them. Public transport is a fairly distant concern for most of them. Oil companies increase crude prices to get on the gravy train, so does every other entity in the industry. Car dealerships jack up prices because they want to maintain their profit levels. Meanwhile middle class people who rely on cars get effed.
      - hooverd 3y ago
        Nah, you do congestion pricing in cities where transit is feasible.
jcranmer 3y ago
You don't ride buses much do you? Of all the times I've ridden regular bus routes, there's only been one route where the bus being 90% empty would not be extremely atypical--and even then, that was only when I was picking up the bus during off-peak hours. More frequent have been the times where there being anything other than standing room available was the atypical situation. If you're in an urban environment at least as densely packed as, say, San Jose, then the bus system is likely to have actually quite substantial ridership. By the time you get to the kinds of dense urban environments of the standard major US cities (NYC, Chicago, DC, Philly, Boston), I quite assure that the buses are routinely packed. The story might be different if we're talking about, say, Bismarck. Furthermore, I should point out that if a bus is stopped "pil[ing] up traffic behind them", that's because it's letting passengers embark or disembark, which is a strong signal that the bus probably isn't 90% empty.
- josephcsible 3y ago
  > Of all the times I've ridden regular bus routes, there's only been one route where the bus being 90% empty would not be extremely atypical You're falling victim to the inspection paradox: https://towardsdatascience.com/the-inspection-paradox-is-everywhere-2ef1c2e9d709 https://towardsdatascience.com/the-inspection-paradox-is-eve...
  - Freedom2 3y ago
    Interesting. What evidence do you have to back up your claim that the user has fallen victim to this paradox?
    - josephcsible 3y ago
      Using your experience as a passenger to gauge how full buses usually are is about as straightforward of an example of that paradox as you could ask for. As an extreme example, imagine there are 10 bus routes, 9 of which are always empty and 1 of which is always full. If you surveyed every passenger, they'd tell you that 100% of the buses they've ever been on are full, but in reality, only 10% of the buses are.
Zigurd 3y ago
On-demand AVs will probably kill mass transit in the US. The poor will get the equivalent of EBT cards to ride, so there will be a social aspect to it. But framing it as some kind of Randian triumph ignores that there are places in the world where mass transit is very efficient because the cities are different. Private cars will be for the rich and should be taxed appropriately. Meeting your fellow citizen while riding an AV mini-bus will open your eyes to social diversity.
caditinpiscinam 3y ago
There are tons of real-world situations in which individuals, by making choices that benefit themselves, create a situation that is worse for everyone overall. It's basic microeconomics https://en.wikipedia.org/wiki/Tragedy_of_the_commons https://en.wikipedia.org/wiki/Tragedy_of_the_commons

cs702 3y ago

Please don't editorialize the title. The original title is actually "Basics: Technology Never Changes Geometry." The OP's main point is that in dense urban areas, replacing high-capacity vehicles with small-capacity ones presents a geometric challenge, because the surface area covered by streets is fixed. Were we to replace every bus carrying an average of, say, 40 people, with 20 small self-driving vehicles, each carrying an average of two people, the street surface area occupied by the small vehicles will be significantly greater and traffic will slow down to a crawl. Imagine a gazillion small vehicles stopping everywhere to pick up and drop off passengers. As the OP correctly points out, finding ways to use space efficiently is the core problem of urban transportation.

Phil_Latio 3y ago
The additional vehicles could simply drive around the "hot" zones...
quantumwannabe 3y ago
The author forgot about time. 20 small self-driving vehicles that come every 30 seconds uses no more road space than a 40-person bus that comes every 10 minutes. Musk's self-driving taxi idea also isn't new. It's essentially the same thing as Personal Rapid Transit [1] which was originally envisioned back in the 1950s as a way to solve real world public transit system issues: >Most mass transit systems move people in groups over scheduled routes. This has inherent inefficiencies. For passengers, time is wasted by waiting for the next vehicle to arrive, indirect routes to their destination, stopping for passengers with other destinations, and often confusing or inconsistent schedules. Slowing and accelerating large weights can undermine public transport's benefit to the environment while slowing other traffic. >Personal rapid transit systems attempt to eliminate these wastes by moving small groups nonstop in automated vehicles on fixed tracks. Passengers can ideally board a pod immediately upon arriving at a station, and can – with a sufficiently extensive network of tracks – take relatively direct routes to their destination without stops [1] https://en.wikipedia.org/wiki/Personal_rapid_transit https://en.wikipedia.org/wiki/Personal_rapid_transit
- jcranmer 3y ago

fooker 3y ago

If policy makers had the authors perfect understanding of geometry : * We would be living in tiny cubicles and sharing amenities with N people (N is a function of whatever factors the authorities deem important.) * Strapped to vertical planks for flights. * Have perfectly circular(/spherical?) cities with poorer people commuting from farther rings. * Work in tiny cubicles (This has already happened, thanks beancounters!). * Children carted away to boarding schools to not disrupt routines of productive people and ensure optimal education (sounds familiar?). * Industrial workers deployed to worksites for N months (N is a function beyond your control..)

Tade0 3y ago
My city's traffic planners designed the traffic light phases with safety (and possibly throughput) as their primary concern. Apologies for the caps, but I have very strong feelings about this: THERE'S NOT A SINGLE INTERSECTION THAT I CAN WALK THROUGH IN ONE PHASE People being people just go on red. Drivers run through intersections way past late amber - especially on left turns. Someone assumed spherical humans in a vacuum and is probably happy with the results.

Zigurd 3y ago

there are a few problems with the article: first, busses in US cities are either too full on clogged streets or too empty on empty streets to have an average load factor high enough to make them less polluting than cars. Cars. even ordinary sedans, used as shared robotaxis could readily beat busses environmentally. But once you get purpose-built mini-bus robotaxis, that will dominate in efficiency. I'm all for better social amenities, but, in the US, with maybe a couple exceptions, robot-rides-on-demand is the likely winner, and it will be a near ideal free market: No barriers to entry, relatively low capex to get started, intermediaries enabling any size fleet to get customers, etc.

pierat 3y ago

And by the time you explain it, you've already lost the narrative. A fact that we've learned in the massive social media sphere is that "Louder = right". And, I hate this. Someone screams their viewpoint? They must be right. Someone responds back with trite phrases that catch people? Obviously correct. Someone retorts with an overly simplistic comment? Of course, naturally correct. Someone exerting power in a situation against someone with little power? Might makes right.

Tade0 3y ago

> Musk assumes that transit is an engineering problem, about vehicle design and technology. In fact, providing cost-effective and liberating transportation in cities requires solving a geometry problem. This confusion is very common in transport technology circles. It's actually a psychology problem and I wish more urban/transit planners understood that. You'd be hard-pressed to make buses go bumper to bumper like cars in traffic, meaning there's space to spare even when most people use public transport to move around. Geometry is actually a constraint only on the terminals - parking lots consume a lot of land. Meanwhile people choose to drive not because it's efficient (it's not, far from it), but because for them it has advantages which can't be summarized as a single number like average travel time. If you ask around you'll find that most people don't think too hard about the exact amount of minutes their commute takes. They just want to be on time and once that's taken care of, other factors become more important. To solve this you have to change how public transport is perceived. I'm not American so bear with me here: One way to do it is to give a familiar experience. If statistics are to be believed, half of US K-12 students get to school by bus. Also, people regularly fly. Private transport via air is comparatively rare. This is all mass transit. To me the core features of these two experiences are: -Everyone sits. -Everyone is accounted for. -Changes are minimized, if present at all. -There's a schedule and it's treated seriously. It appears that Elon Musk, despite being generally unhinged, knows more about human nature than transit planners, which is weird, because that's a low bar to clear.